Carbon holder



CARBON HOLDER Filed March 3, 1945 INVENTOR ATTORN Y Patented Sept. 17, 1946 UNITED STATES PATENT OFFICE CARBON HOLDER. Arthur T. Steingard, New York, N. Y.

Application March 3, 1945, Serial No. 580,853

. .1 This invention relates to projection lamps and similar apparatus employing carbons for producing an arc. More particularly, the invention relates to a device for supporting what I term short-end carbons in machines of the class described to provide for the consumption thereof.

Still more particularly, the invention relates to.

a holder of the class described employing means checking feed of the positive carbon to minimize the degree of burning of the holder, as well as in the provision of means of checking movement of a carbon ejector plunger employed in the device.

Thenovel-features of the invention will be best understood from the following description, when taken together with the accompanying drawing, in which certain embodiments 'of the invention are disclosedand, inwhich, the separate parts. are designated by suitable reference characters in each of the views and in which:

Fig. l is a diagrammatic side view illustrating a part of a projection lamp, showing one form of holder which I employ.

Fig. 2 is an enlarged sectional view of the holder shown in Fig. l'detached.

Fig. 3 is a bottom plan view of a modified form of holder which I employ.

Fig; 4 is a section on the line 4-4 of Fig. 3; and l Fig. 5 is a section on the line 5-5 of Fig. 3.

In projection lamps such for example as the Ashcraft lamp and other apparatus of this kind, it has been customary to use long positive carbons which are automatically fed through a mechanism in the direction of a negative carbon in the operation of the apparatus and, in this procedure, relatively long endsare left unburned and have been discarded or attempts have been made to use the same with adaptor holders. These ends, for purposes of description, are referred to as short-ends, and it isthe purpose of my invention to provide a holder for short-end positive carbons by means of which the shortend may be consumed to the greatest possible degree and in a manner minimizing the burningoff of the end of the holder. At the same time, I provide a holder having means for automatically stopping feed of the positive carbon, as well as means for checking movement of an ejece tor pin in the holder in removing the stub end of'the burned carbon from the holder.

In Fig. 1 of the drawing, I have diagrammatically illustrated part of the mechanism of an Ashcraft projection lamp and, in this figure, I ll represents a base, in which is arranged a guide rod or rods upon which is mounted a slide 13 Claims. (01. 176 -119) l2, the slide at its upper end carrying a. clamp l3 normally used to clampa long positive carbon for feed in thedirection of a negative carbon I4 supported in aguide by a clamp IS, the latter being only partially shown. At I1 is shown a suitably supported positive carbon guide, in which a short-end positive carbon I8 is adapted to be supported and guided in its movement in the direction of the negative carbon l4.

At I9 is shown: one of my improved carbon holding devices comprising an elongated tube 20, one end'portion of which is slightly reduced, as seen at 2|, to receive a sleeve 22 which fits snugly on the reduced end 2| and is held in place by riveting-over the end of the tube, as seen at 23 in Fig. 2 of the drawing. The tube 20 and sleeve 22 have registering threaded apertures 24 for receiving a set screw 25. V

The tube 20 has a bore 26 of common diameter throughout the length thereof and fitting in this bore is a rod 21, the end portion 28 of which is adapted to be secured in the clamp l3, as shown in Fig. 1 of the drawing. The other end portion of the rod 28 has a downwardlyextending stop pin 29 which operates in an elongated aperture 30 in the tube20. The aperture 30 forms a split in the tube which terminates in a crosscut aperture 3| adjacent the sleeve 22. r The crosscut aperture 3| gives greater spring properties to the split portion of the sleeve to firmly grip the carbon I8 in the end portion thereof in the manner clearly illustrated in Fig. 2 of the drawing. This end of the tube 20 is also preferably rounded, as seen at 32, to facilitate passage through the recess of the guide ll in the movement of the positive carbon and the holder in the direction of the negative carbon M.

The stop pin 29 is preferably so spaced with respect to the end of the rod 21 as to gauge the distance of spacing of the end of the holder with respect to the negative carbon, with the end of the rod 21 abutting the inner end of the carbon held in the holder Hi. In this way, the greatest possible consumption of the carbon is provided with a minimum amount of burning-off of the end of the holder, as experienced in devices of this kind. In this connection, it will be understood, however, that as the splitend of the holder burns-off, it can be re-ground or rounded, as at 32, to a point closely adjacent the cross or transverse aperture. 3| or to the point where the tube 20 has sufficient spring properties to grip and hold a carbon therein. This burning-off will also be checked by the pin 29 engaging the inner end.

,of the aperture or split 30.

fashion and may be performed with the rod secured in the clamp or with the rod detached from the clamp 13.

In Figs. 3 and 4 of the drawing, I have shown a diirerent form of holder 34 wherein a tube 35, similar in some respects to the tube 20, is em= ployed with the exception that the tube 35 is made considerably longer and has at one end portion a split 36, similar to the split 30, and across-cut aperture 31 at the base of the split. Ifhe sleeve 22 is dispensed with and, instead, the tube is provided with an extendedend portion 38 spaced from the split end portion bya solid or annular wall part 39, the end portion 38 having anelongated aperture 40 therein, through which a stop pin 'rl, similar to the pin 33, passes and through which a clamp screw 42! also-passes. The pin M and screw '42 are ,both in threaded engagement with a rod 33, similar to the rod 21, and to this rod is also secured a, stop pinlid, similar to the pin 29. It will also appear that the aperture 40 terminates short of the end 36 of the tube 'to form an annular collar portion 4-5 at said end which retains the rod 43 against displacement from the tube, 35 and also limits movement of the rod in one directionin the tube. The screw 42 is adapted to draw the rod firmly upon one wallof the tube in the manner illustratednin the enlarged cross-sectional view of Fig; in retaining the rod against relative movement, particularly in the feed of the positive carbons 18 in the-machine, in the manner previously described,

It will also appear that, upon loosening the screw 42, the rod is freed for movement longitudinally of the tube for ejecting a carbon stub and in the re-setting of the rod when a new carbon has been inserted into position; I V

In both forms of the construction, the bore of the tube of the holder is the'same throughout its length and this is particularly important at the split end thereof, so as to provide the long use of the holder as the split end slowly burns off. However, .by using metals capable of withstanding the high temperature, the tendency to burn off is minimized, thus, giving long life and service to the holder.

Considering the structure shown in Figs; 3 and 4 of the drawing, it will be apparent that the holder comprises, primarily, simply a tube and a rod, in addition to the stop pins and clamp screw employed. This provides a very simple form of construction and dispenses with the necessity of shaping the tube and setting the sleeve thereon, as taught in- Figs. 1 and2'.

Carbons of'the type and kind under consideration are made in different diameter sizes and it will be apparent that the holders will be made to suit the different size of carbons employed.

It might also be found desirable to ore-fabr'icate carbons to a length for main the holder and calculated to control a predetermined operation of the machine with a small stub end remaining on completion of the machine operation.

Having fully described my invention, what I claim as new and-desire to secure by Letters Patent is l. A carbon holder comprising a tube, said tube tube and a carbon mounted therein, and a stop I adjacent the first named end portion of the tube adapted to engage stationary member for limiting movement of the tube in the direction of said member.

' 2. A carbon holder comprising a tube, said tube having a bore of common diameter throughout the length thereof, one end portion of, the tube being split to provide clamping engagement with a carboninserted in said split end, a rod mounted in said tube, means clamping the rod against movement relatively to the tube, with one end portion of the rod protruding beyond the other end of said tube to form means supporting the tube and a carbon mounted therein, a stop adjacent the first named end portion of the tube adapted to engage a stationary member for limiting movement of the tube in the direction of said member, and means on said rod operatively engaging the tube to check movement of the rod in one direction in said tube.

3. A carbon holder comprising a tube, said tube having a bore of common diameter throughout the length thereof, one end, portion of the tube being split to provide clamping engagement with a carbon inserted in said split end, aro-dmounted in said tube, means clamping the rod against movement relatively toythe tube with one end portion of the rod protrudinglbeyond the other end of said tube to form means supporting the tube, a stop adjacent the first named end portion of the tube adapted to engage astationary member for limiting movement, of the tube in the direction of said member, means on said rod operatively engaging the tube to check movement of the rod in one direction in said .tube, and said last named means and stop .both comprising pins secured to said rod.

4. A carbon holder comprising a tube; said tube having a bore of common diameter through-: out the length thereof, one end portion of'the tube being split to provide clamping engagement with a carbon inserted in said split end, a rod mounted in said tube, means clamping the rod against movement, relatively to the tube with one end portion of the rod protrudingbeyond the other end of said tube toform means supporting the tube, a stop adjacent the firstnamed end portion of the tube adapted to engage a stationary member for limiting movement of the tube in the direction of said member, means on said rod operatively engaging the tube to check movement of the rod in one direction in said tube, said last named means and stop both com prising pins secured tosaid rod, andsaid clamping means comprising a screw engaging said rod.

5. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion'of the tube having an elongated slot terminating at its inner end in a crossslot, the slottedend of the tube giving spring properties thereto for gripping a carbon therein, 7

a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, and means for clamping the rod within the tube in controlling the position of said pin with respect to the first named end of the tube.

6. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion of the tube having an elongated slot terminating at its inner end in acrossslot, the slotted end of the tube giving spring properties thereto for gripping a carbon therein, a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, means for clamping the rod within the tube in controlling the position of said pin with respect to the first named end of the tube, the other end portion of the tube having an elongated iaperture, and said clamping means comprising a screw engaging the rod and operating in the aperture of said tube.

7. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion of the tube having an elongated slot terminating at its inner end in a cross-slot, the slotted end of the tube giving spring properties thereto for gripping a carbon therein, a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, means for clamping the rod within the tube in controlling the position of said pin with respect to the first named end of the tube, the other end portion of the tube having an elongated aperture, said clamping means comprising a screw engaging the rod and operating in the aperture of said tube, and another pin coupled with the rod and operating in said last named aperture and adapted to check movement of the rod in one direction in said tube.

8. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion of the tube having an elongated slot terminating at its inner end in a crossslot, the slotted end of the tube giving spring properties thereto for gripping a carbon therein, a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, means for clamping the rod within the tube in controlling the position of said pin with respect to the first named end of the tube, the other end portion of the tube having an elongated aperture, said clamping means comprising a screw engaging the rod and operating in the aperture of said tube, another pin coupled with the rod and operating in said last named aperture and adapted to check movement of the rod in one direction in said tube, the central portion of the tube being circumferentially continuous, and said tube having common inside and outside diameters throughout the length thereof.

9. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion of the tube having an elongated slot terminating at its inner end in a crossslot, the slotted end of the tube giving spring properties thereto for gripping a carbon therein, a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, a sleeve mounted on the other end portion of said tube, means retaining the sleeve against displacement on the tube, and a clamp screw passed through said sleeve and tube and engaging the rod to secure said rod in dififerent positions in said tube.

10. A carbon holder for machines of the class described, said holder comprising an elongated tube, one end portion of the tubehaving anelongated slot terminating at its inner end in a cross-slot, the slotted end of the tube giving spring properties thereto for gripping a carbon therein, a rod mounted in said tube, said rod having a pin member operating in the slot of said tube, a sleeve mounted on the other end portion of said tube, means retaining the sleeve against displacement on the tube, a clamp screw passed through said sleeve and tube and engaging the rod to secure said rod in different positions in said tube, and means on the rod outwardly of the last named end of the tube adapted to check movement of the rod in the direction of the first named end of said tube.

11. The combination with a projector lamp of the class described having a slide with means for clamping a carbon therein, a carbon guide spaced with respect to said slide, of a carbon holding device comprising a rod, one end portion of which is adapted to be secured in the clamp of said slide, a tube slidably engaging the other end portion of said rod, means adjustably clamping the tube on said rod, means supporting a carbon in said tube, and a stop on said rod adapted to engage said guide in limiting movement of the slide in the direction of said guide.

12. The combination with a projector lamp of the class described having a slide with means for clamping a carbon therein, a carbon guide spaced with respect to said slide, of a carbon holding device comprising a rod, one end portion of whichis adapted to be secured in the clamp of said slide, a tube slidably engaging the other end portion of said rod, means adjustably clamping the tube on said rod, means supporting a carbon in said tube, a stop on said rod adapted to engage said guide in limiting movement of the slide in the direction of said guide, and means on said rod checking movement of the tube in one direction thereof.

13. The combination with a projector lamp of the class described having a slide with means for clamping a carbon therein, a carbon guide spaced with respect to said slide, of a carbon holding device comprising a rod, one end portion of which is adapted to be secured in the clamp of said slide, a tube slidably engaging the other end portion of said rod, means adjustably clamping the tube on said rod, means supporting a carbon in said tube, a stop on said rod adapted to engage said guide in limiting movement of the slide in the direction of said guide, means on said rod checking movement of the tube in one direction thereof, the carbon supporting means of the tube comprising a split end portion of the tube, and said adjustable clamp means comprising a screw engaging said rod.

ARTHUR T. STEINGARD. 

